A directed acyclic graph has a topological ordering. This means that the nodes are ordered so that the starting node has a lower value than the ending node. A DAG has a unique topological ordering if it has a directed path containing all the nodes; in this case the ordering is the same as the order in which the nodes appear in the path.

In computer science, DAGs are also called wait-for-graphs. When a DAG is used to detect a deadlock, it illustrates that a resources has to wait for another process to continue.